Quarter	Units
1982-04-01	16895
1982-07-01	19682
1982-10-01	38979
1983-04-01	17526
1983-07-01	19815
1983-10-01	36873
1984-04-01	18021
1984-07-01	18807
1984-10-01	33604
1985-04-01	17566
1985-07-01	18682
1985-10-01	36259
1986-04-01	11476
1986-07-01	16822
1986-10-01	41130
1987-04-01	10480
1987-07-01	15172
1987-10-01	31548
1988-04-01	10499
1988-07-01	13887
1988-10-01	26180
1989-04-01	12731
1989-07-01	12166
1989-10-01	26590
1990-04-01	12056
1990-07-01	11984
1990-10-01	19731
1991-04-01	10159
1991-07-01	8059
1991-10-01	14946
1992-04-01	6377
1992-07-01	6116
1992-10-01	13314
1993-04-01	6809
1993-07-01	4980
1993-10-01	9124
1994-04-01	6765
1994-07-01	4928
1994-10-01	9254
1995-01-01	3089
1995-04-01	4456
1995-07-01	5587
1995-10-01	11589
1996-01-01	3717
1996-04-01	4875
1996-07-01	7126
1996-10-01	12539
1997-01-01	3743
1997-04-01	4769
1997-07-01	6877
1997-10-01	12741
1998-01-01	3137
1998-04-01	3486
1998-07-01	4371
1998-10-01	9329
1999-01-01	2602
1999-04-01	3221
1999-07-01	3651
1999-10-01	9813
2000-01-01	2622
2000-04-01	3121
2000-07-01	3368
2000-10-01	12472
2001-01-01	3973
2001-04-01	4209
2001-07-01	5494
2001-10-01	14378
2002-01-01	4756
2002-04-01	5259
2002-07-01	5727
2002-10-01	15769
2003-01-01	4437
2003-04-01	4744
2003-07-01	6227
2003-10-01	20135
2004-01-01	6869
2004-04-01	6790
2004-07-01	8680
2004-10-01	21574
2005-01-01	7288
2005-04-01	7814
2005-07-01	8176
2005-10-01	17806
2006-01-01	7118
2006-04-01	5877
2006-07-01	5805
2006-10-01	15064
2007-01-01	5484
2007-04-01	7697
2007-07-01	7391
2007-10-01	15587
2008-01-01	5751
2008-04-01	5387
2008-07-01	9227
2008-10-01	15710
2009-01-01	6617
2009-04-01	6464
2009-07-01	7187
2009-10-01	11726
2010-01-01	4824
2010-04-01	3793
2010-07-01	4618
2010-10-01	7588
2011-01-01	3141
2011-04-01	2444
2011-07-01	2562
2011-10-01	4508
2012-01-01	2444
2012-04-01	2019
2012-07-01	2046
2012-10-01	4051
2013-01-01	1123
2013-04-01	1557
2013-07-01	1397
2013-10-01	3216
